[1] UCL Inst Neurol, MRC Ctr Neuromuscular Dis, Queen Sq, London, England
[2] Natl Hosp Neurol & Neurosurg, Queen Sq, London, England
[3] St Georges Univ Hosp NHS Fdn Trust, Clin Genet Dept, London, England
[4] St George Hosp, Atkinson Morley Reg Neurosci Ctr, Dept Neurol, London, England
[5] St George Hosp, Atkinson Morley Reg Neurosci Ctr, Dept Neuroradiol, London, England
[6] St Helier Hosp, South West Thames Renal & Transplantat Unit, Carshalton, Surrey, England
[7] St Helier Hosp, South West Thames Inst Renal Res, Carshalton, Surrey, England
[8] St Georges Univ NHS Fdn Trust, South West Thames Reg Genet Serv, London, England
[9] UCL Great Ormond St Hosp Children, Dubowitz Neuromuscular Ctr, Div Neuropathol, London, England
[10] Natl Hosp Neurol & Neurosurg, Div Neuropathol, Queen Sq, London, England
[11] Cambridge Univ Hosp NHS Fdn Trust, Addenbrookes Hosp, Dept Histopathol, Neuropathol, Cambridge, England
[12] UCL Inst Child Hlth, Dubowitz Neuromuscular Ctr, Paediat Neurol, London, England
[13] Great Ormond St Hosp Sick Children, London, England